Top 22 Most Downloaded Python Packages and Their Core Features

This article surveys the 22 most downloaded Python packages on PyPI over the past year, explaining each library's primary purpose, typical use cases, download statistics, and offering short code snippets that demonstrate their core functionality.

1. urllib3 – an advanced HTTP client offering thread safety, connection pooling, SSL/TLS verification, multipart file upload, proxy support, and compression handling (8.93 billion downloads). It underlies many higher‑level libraries such as requests .

2. six – a compatibility layer that enables code to run on both Python 2 and Python 3 (7.32 billion downloads). It provides utilities like six.print_() to mask syntax differences.

3. botocore, boto3, s3transfer, awscli – a group of AWS‑related libraries (combined downloads exceed 15 billion). botocore is the low‑level core, boto3 offers a high‑level SDK for services such as S3 and EC2, s3transfer manages multipart transfers, and awscli provides the command‑line interface.

4. pip – the standard package installer for Python (6.27 billion downloads). It supports simple commands like pip install <package> and works with requirements.txt and virtual environments.

5. python-dateutil – extends the built‑in datetime module with powerful parsing and timezone handling (6.17 billion downloads). Example usage: from dateutil.parser import parse .

6. requests – a user‑friendly HTTP library built on top of urllib3 (6.11 billion downloads). Simple GET request example: import requests\nr = requests.get('https://api.github.com/user') .

7. s3transfer – manages S3 data transfers; often used indirectly by boto3 and awscli (ranked 7th).

8. certifi – provides a curated collection of root SSL certificates for verifying HTTPS connections (5.52 billion downloads).

9. idna – implements the Internationalized Domain Name (IDN) protocol, enabling conversion between Unicode and ASCII domain representations (5.27 billion downloads). Example: import idna\nidna.encode('ドメイン.テスト') .

10. PyYAML – a YAML parser and emitter that can read/write YAML files and map them to native Python objects (5.25 billion downloads).

11. pyasn1 – a pure‑Python implementation of ASN.1 encoding/decoding, used by many security‑related packages (5.12 billion downloads).

12. docutils – a modular system for converting plain‑text documentation into formats like HTML, XML, and LaTeX (5.08 billion downloads). It powers tools such as Sphinx.

13. chardet – detects character encodings in byte streams, useful for handling unknown text data (5.01 billion downloads). Command‑line usage: chardetect file.txt .

14. rsa – a pure‑Python implementation of the RSA algorithm, supporting encryption, decryption, signing, and key generation (4.92 billion downloads). Example key generation and encryption shown with import rsa .

15. jmespath – a query language for extracting data from JSON structures (4.73 billion downloads). Example: import jmespath\nprint(jmespath.search('foo.bar', d)) .

16. setuptools – the de‑facto tool for building and distributing Python packages (4.01 billion downloads).

17. awscli – the official Amazon Web Services command‑line interface (ranked alongside other AWS libraries).

18. pytz – provides accurate and cross‑platform timezone definitions (3.94 billion downloads). Example: from pytz import timezone\nams = timezone('Europe/Amsterdam') .

19. futures – a backport of the concurrent.futures module for Python 2, enabling thread‑pool and process‑pool execution (3.89 billion downloads).

20. colorama – adds cross‑platform colored terminal text support (3.70 billion downloads). Example: from colorama import Fore\nprint(Fore.RED + 'red text') .

21. simplejson – a fast JSON encoder/decoder compatible with the standard library but offering better performance and broader version support (3.41 billion downloads).

22. boto3 – the high‑level AWS SDK for Python, tightly coupled with botocore and other AWS tools (ranked with the other AWS packages).

The article concludes that many top‑ranked packages provide core functionality such as networking, data handling, encryption, and tooling, and they are frequently dependencies for other projects.